The Climate Change Authority has warned the Government's own climate policy is at risk of becoming fiscally "unsustainable".

A report released today, called Australia's Climate Policy Options, assesses different ways of reducing greenhouse gases, using examples from around the world.

It says Australia's Emissions Reduction Fund falls into the category of voluntary government purchase of emissions reductions.

It says this type of policy has advantages including relatively low indirect and transaction costs, but that at a larger scale the "fiscal cost could become unsustainable".

"Good policies reduce emissions at low cost and can be readily scaled up to achieve greater emissions reduction if and when needed," said the acting chair of the Climate Change Authority, Stuart Allinson.

"Policies with these characteristics are more likely to attract broad support and provide a stable and predictable basis for new, long-lived investments."

"We are able to bring to this meeting success in our 2020 targets," he told the ABC this morning.

"We've set out an ambitious target and a credible target, a pathway to meet it, we are meeting it."

But Mr Allinson said Australia would "need new policies to achieve its targets to 2030 and beyond".

"The authority is of the view that it is time for a fresh look at the range of policy options, including the various forms of emissions trading schemes with a view to 'resetting' Australia's public discussion," he said.

"Among policy options, emissions trading is important and can take many forms."

The Climate Change Authority is an independent government agency established by the Gillard government in 2011. Its role is to provide policy advice on climate change to government.

The Government sought to abolish the authority in 2013 but were thwarted by the Senate.